Welcome to NUEWO

NUEWO is entirely dedicated to the Internet and to all aspects of this issue. We consider in detail all the facets of the Internet, such as the DNS, email messaging, privacy on the Internet, and many more.

The Domain Name System

IP defines two mechanisms for identifying nodes: the IP address and the fully qualified domain name. The IP address is a globally unique 32-bit value that indicates where the node is attached to the Internet (or intranet). The fully qualified domain name (FQDN) is a globally unique host name and domain that also indicates where the node is attached. An important difference between these two identifiers is that the IP address is necessary, while the name is not. Network devices like routers require an IP address to deliver packets, while the IP host name is most useful for humans as well as for giving a network resource or service a name that is independent of network topology (the hosting server may change, but the name can remain the same). When the first IP networks were built, host names could be associated with IP addresses by maintaining a file on every system that contained a list of all connected IP hosts with their IP addresses. On relatively small and static networks, the hosts file need be updated only when a host is added, removed, or moved around in the network. On slightly larger networks, an authoritative hosts file can be maintained on some central server and uploaded periodically by all network hosts. However, this approach rapidly fails to scale as network size increases. First, as the network size increases, so does the size of the hosts file, causing the periodic downloads to be longer and longer for each individual node and requiring an ever-more powerful central hosts file server. Second, as the network increases in size, downloading the hosts file takes up more and more bandwidth. Not only is the file larger, but it must also go to a greater number of nodes, across more and more networks. Finally, the growth of the net- work means also that more changes occur more frequently, causing more network problems reaching nodes that have just recently been added or moved as well as problems reaching nodes that have been removed from the network.